"Lithography at Small Dimensions: Do We Need Polymers Anymore?"November 2nd, 2006

High resolution lithography, the key process step used in manufacturing microelectronics, is at an important juncture. Traditional polymer photoresists have molecular dimensions comparable to that of the target pattern dimensions. These overlapping length scales are requiring a rethink of the methods used to create nanostructures and may not need polymers.

An example of such non-polymeric materials, molecular glasses are a family of glass forming organic molecules that only recently have been investigated as high-resolution photoresists. Design concepts come largely from the organic electronics community where these materials have been investigated as new, glass forming semiconductors. As studied these materials are of limited molecular dimension (molecular size on the order of 1 nm). Molecular glasses offer process opportunities not possible with polymers.

Another promising example of new lithographic strategies makes use of the self-assembly characteristics of block copolymers. These materials produce periodic patterns of only a few 10s of nm and are being explored for design of structures that cannot be produced today using high resolution lithography. Efforts to create block copolymers that incorporate photosensitive characteristics will be described.

The control of the physicochemical properties of surfaces in contact with biological systems represents a fundamental issue in many applications ranging from coatings to biotechnology and microelectronics. In particular, advances in biotechnology depend on the ability to fashion materials with precise control of feature size and functionality. This presentation focuses on issues of specific and non-specific binding and strategies being developed to control both. Examples of specific binding that enable investigation of cell function will be presented. The broader issue of non-specific binding and how it relates to fouling release will also be discussed in terms of surface structure. New coatings that make use of recent discoveries in improved fouling release based on dynamic surfaces will be described. These materials may form the basis of environmentally friendly fouling release coatings for marine and biomedical applications.